<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    .list-item {
      display: inline-block;
      margin-right: 10px;
    }
    .list-enter-active, .list-leave-active {
      transition: all 1s;
    }
    .list-enter, .list-leave-to
    /* .list-leave-active for below version 2.1.8 */ {
      opacity: 0;
      transform: translateY(30px);
    }
    /* ，它会在元素的改变定位的过程中应用 */
    .list-move {
      transition: transform 1s;
    }
  </style>
  <script src="../../dist/vue.min.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.14.1/lodash.min.js"></script>
</head>
<body>
  <div id="list-demo" class="demo">
    <button v-on:click="shuffle">Shuffle</button>
    <button v-on:click="add">Add</button>
    <button v-on:click="remove">Remove</button>
    <!-- 默认span标签展示，可以通过tag更换标签 -->
    <transition-group name="list" tag="p">
      <span v-for="item in items" v-bind:key="item" class="list-item">
        {{ item }}
      </span>
    </transition-group>
  </div>

  <script>
  new Vue({
    el: '#list-demo',
    data: {
      items: [1,2,3,4,5,6,7,8,9],
      nextNum: 10
    },
    methods: {
      randomIndex: function () {
        return Math.floor(Math.random() * this.items.length)
      },
      add: function () {
        this.items.splice(this.randomIndex(), 0, this.nextNum++)
      },
      remove: function () {
        this.items.splice(this.randomIndex(), 1)
      },
      shuffle: function () {
        this.items = _.shuffle(this.items)
      }
    }
  })
  </script>
</body>
</html>